1. Field of the Invention
The present invention relates generally to an apparatus and method for handling and storing data cartridges, and in particular to a data cartridge handling apparatus and method that is selectively expandable to increase storage capacity.
2. Description of the Related Art
Data storage and handling devices, which are sometimes known as auto-loaders, are systems that include a cartridge read/write drive for writing data to a cartridge and for reading the data from the drive. The data storage and handling devices typically also include one or two cartridge storage magazines that have spaces in which data cartridges that are used by the read/write drive are stored when not in use. A robotic cartridge moving apparatus, also referred to as a cartridge shuttle, is provided for moving the cartridges from the storage magazine to the read/write drive and back again as needed. A power supply and control apparatus are also provided. The data storage and handling device is contained within a housing, such as a standard size, rack-mountable housing.
The demand for data storage capacity for computer systems is constantly increasing. To address the increasing demand, new and larger data backup and archive systems are needed. However, the larger backup and storage systems are expensive to purchase for the user and expensive to manufacture and develop for the manufacturer. If a user has a growing need for higher data storage capacity, it would be a better solution to provide a smaller data storage system to meet present needs that at a later stage can be expanded into a bigger system to meet the greater future needs. One such approach is to provide a data storage system that can be built together for form a bigger system in order to follow the user's growing needs. In this way, the initial investment by the user in the smaller data storage system would not be lost and the additional investment by the user in the expanded data storage system would follow the increased user needs for increased data archive.
There are some data storage systems today that offer the possibility of expanding capacity, but the upgrade is expensive and in some cases involves providing an additional robotic cartridge handling apparatus or mechanism to pass the data cartridges between one or more vertical storage units. Furthermore, some of the expanded capacity systems are physically linked together as a whole, which makes them difficult to ship, handle and install.